Bridge joint seals

ABSTRACT

Elongated, hollow elastomer seals particularly useful for the sealing of bridge deck joints, bridge approach joints and like wide joints against intrusion by liquids and imcompressible solids and embodying a transversely concave top wall; a substantially horizontal bottom wall embodying folding foot portions along the respective longitudinal edges thereof; substantially planar side walls, and an internal web network having downwardly diverging webs in the transversely medial portion of the network and diverging from an apex below the longitudinal midportion of said top wall, two or more pairs of laterally extending webs extending between said diverging webs and respective side walls, a pair of diagonally downwardly and outwardly sloping webs extending respectively between intermediate portions of the top wall and intermediate portions of the uppermost pair of laterally extending webs, and optionally a further shallow V-web extending between the legs of said diverging webs.

United States Patent Brown I 45 Aug. 29, [54] BRIDGE JOINT SEALS [72] lnventor: Delmont D. Brown, North Balti- STRACT more, Ohio 45872 Primary Examiner-Jacob L. Nackenoff AttorneyJohnston, Root, O'Keeffe, Keil, Thompson & Shurtleff Elongated, hollow elastomer seals particularly useful for the sealing of bridge deck joints, bridge approach joints and like wide joints against intrusion by liquids and imcompressible solids and embodying a transversely concave top wall; a substantially horizontal bottom wall embodying folding foot portions along the respective longitudinal edges thereof; substantially planar side walls, and an internal web network having downwardly diverging webs in the transversely medial portion of the network and diverging from an apex below the longitudinal midportion of said top wall, two or more pairs of laterally extending webs extending between said diverging webs and respective side walls, a pair of diagonally downwardly and outwardly sloping webs extending respectively between intermediate portions of the top wall and intermediate portions of the uppermost pair of laterally extending webs, and optionally a further shallow V-web extending between the legs of said diverging webs.

9 Claims, 4 Drawing Figures Patented Aug. 29, 1972 INVENTOR DELMONT D. BROWN A ORNEYS 1 BRIDGE JOINT SEALS RELATED APPLICATION This application concerns improvements in elastomer bridge joint seals of the type disclosed in application Ser. No. 786,889, filed Dec. 26, 1968, by D. R. Honey and F. K. Hall, now U.S. Pat. No. 3,595,141.

SUMMARY OF THE INVENTION This invention concerns improvements in elastomer seals in joints in bridge decks, bridge approaches, and like joints having a relatively large amount of movement during expansion and contraction. The subject seals are particularly suited for sealing of bridge deck joints which have a ledge or seat extending longitudinally on respective opposing faces of said joint. One of the novel features of the subject invention is the provision on the bottom wall of the elongated seal of folding foot portions extending longitudinally along respective longitudinal edge portions of the bottom wall. These folding foot portions are adapted to take the shape of longitudinally extending seats when the subject seals are laterally compressed for insertion into a bridge deck joint or the like. The foot portions also coact to substantially eliminate upward movement of the seal in the joint as it opens and closes under changing environmental temperatures.

The primary purpose of sealing bridge deck joints and like joints is to prevent the infiltration of and accumulation of sand, gravel and/or other incompressibles in the joint and thereby preventing the joint from closing on expansion of the bridge deck and/or its supporting structure in warm weather. Another important reason for sealing such joints is to prevent the infiltration of and flow through in bridge .deck joints of rain water, or melted snow and/or ice. Water in general, and particularly water carrying dissolved chemicals such as solids to deice or prevent ice on bridge decks, is detrimental to metal and/or concrete understructures of the bridge. Water infiltration through joints on bridge approaches and the respective ends of bridges can also create-serious problems such as washing away of soil packed against and supporting end piers and end walls of bridge structures.

Seals of the subject invention are capable of exerting a relatively constant lateral thrust against the side walls of the joint from the 50 percent collapsed state to about one-fifth (20 percent) collapse, said percentages being based on the uncollapsed width of the seal. The seals as initially installed preferably should exert at about 20 percent collapse approximately four pounds of thrust per lineal inch of joint. All such seals have a normal width dimension greater than the widest opening expected from the joint over its anticipated movement in the field. When the seal is in its fully collapsed state, it is laterally compressed to the degree that the walls and internal webs lie against each other and preclude further lateral collapse. It is preferable for purposes of best joint design, however, to dimension the seal so that the latter state is approached but not reached when the bridge joint is in its state of maximum closure. When the joint has opened to its widest dimension, it is preferred that the seal be at least -20 percent laterally collapsed, 'i.e., a collapsed width of about 80-85 percent of the uncollapsed or normal'width of the seal.

The subject elongated, hollow elastomer seals have longitudinally elongated top, bottom and side walls defining a hollow, tubular-like elastomer member adapted to be laterally compressed and inserted in the laterally compressed state into joints of the character above described. The lateral or outward web of the side walls of the seal againstthe side walls of the joint is increased by an elastomer internal web structure functioning in coaction with the top, bottom and side walls to provide lines of increased localized thrust along at least the upper and lower edges of the side walls against the side walls of the joint.

The internal'web structure of the subject seals comprises a pair of elongated, downwardly diverging webs in the transversely median portion of the seal as viewed in end elevation or transverse cross section. These diverging webs may be joined directly at their apex with the longitudinal midportion of the top wall. More preferably, however, they are connected at their apex with said longitudinal midportion of the top wall by a vertical, narrow web substantially midway between the side walls. The lower longitudinal edges of the diverging webs are joined with the bottom wall. Additional webs of the internal web structure include webs extending substantially transversely laterally between the direction and are joined at their inner longitudinal edges with the aforesaid downwardly diverging webs. In some embodiments of the invention, the internal struc: ture also includes one or more additional webs extending laterally between the diverging webs which additional webs may be substantially planar, horizontal webs or may have a shallow V-configuration as viewed in end elevation or transverse cross section.

The top wall of the seals herein may be substantially flat but more preferably has a shallow V-configuration at least along the longitudinal midportion thereof. If desired, the entire top wall may have a shallow V-configuration. Furthermore for purposes of effecting a better seal of the upper, longitudinal edges of the side walls with the side walls of the joint, these upper longitudinal edges may have a small, laterally projecting, preferably substantially sharp-edged lip, each of which provides a relatively sharp longitudinal line of localized lateral thrust against the side walls of the joint along the respective upper corners of the seal. The sealing at the upper, longitudinal edges further may be enhanced by an additional pair of diagonally downwardly and outwardly sloping webs extending respectively between intermediate portions of the top wall and intermediate portions of the uppermost pair of laterallyextending webs. This pair of diagonal webs resists downward movement of the intermediate portions of the top wall by pushing" upwardly on intermediate segments of the top wall when the seal is collapsed laterally and thereby keeps the upper, longitudinal corners from rolling inwardly. The concave, V- or U-fold in the top wall occurs essentially in the center segment. The webs retain their essentially straight configuration when the seal is collapsed laterally and thereby'keep the outer top wall segments in a substantially horizontal or slightly upwardly bowed configuration. The bottom wall comprises a longitudinal midportion and the portion and the foot-forming edge portions of the bottom wall.

The foot-forming edge portions of the bottom wall comprise two angulated segments. The outermost strip segment extends transversely downwardly from the lower edge of the bottom wall to a point near and below the longitudinal edges of the longitudinal midportion of the bottom wall. The other segment of the foot-forming longitudinal edges of the bottom wall is a narrower strip.

segment extending transversely diagonally upwardly from the inner longitudinal edge of the respective first strip segment to the contiguous longitudinal edge of the longitudinal-midportion of the bottom wall.

When the subject seals are laterally collapsed, the foot-forming longitudinal edge portions, as viewed in end elevation or transverse cross section, immediately fold into a deeper V-configuration than the initial, nonsymmetric V-configuration of said foot-forming portions. The respective apices of these foot-forming portions are dimensioned so that they will seat upon'the longitudinal ledges or seats of the bridge deck joint when the seal is collapsed to 80 to 85 percent of its normal or unstressed width. As the seal is further collapsed, either during insertion of the seal into the joint or by movement of the jointtoward its narrowest width, the narrower, inner strip segment of the foot-forming portions rotates toward a position wherein it will lie substantially flat on the longitudinal ledge or seat of the bridge deck joint. Simultaneously the longitudinal midportion of the bottom wall folds into a progressively deeper V- or U-configuration.

By virtue of the connection of the bottom wall with a longitudinal midportion v of the top wall via the aforesaid internal web structure, the elastic recovery forces developed upon bending the bottom wall and the other internal web members creates an upward thrust therein. This upward thrust is transmitted through the internal structure of the seal with the result that'elastic recovery forces in the bottom wall push the center portion of the top wall upwardly and thus augment the aforesaid anti-rolling effect provided by the downwardly and outwardly diagonal webs at respective upper corners of the sealing strip.

DESCRIPTION OF DRAWINGS A preferred embodiment of the invention is illustrated in the drawing wherein:

FIG. 1 is an end elevation of a bridge joint, the latter shown in fragment and in substantially fully open position with a preferred embodiment of the subject seals mounted therein;

FIG. 2 is 'an end elevation similar to FIG. 1 with the joint at its substantially fully closed position; and

FIG. 3 is an isometric view of the seal illustrated in FIGS. 1 and 2 in the uncollapsed state thereof; and

FIG. 4 is a second preferred embodiment utilizing the aforesaid pair of diagonally downwardly and outwardly sloping webs extending respectively between intermediate portions of the top wall and intermediate portions of the uppermost pair of laterallyextending webs.

DESCRIPTION OF PREFERRED EMBODIMENT Referring to the drawing, the hollow, elongated,

elastomer seal 10 is mounted in an expansion joint 11 extending transversely across a bridge deck. The joint 11 has vertical, substantially planar,- opposed joint faces 12 and 13. At the bottom edge thereof the joint is stepped inwardly so as to provide longitudinal ledges or seatsv l4 and 15. These joints 11 may be formed from concrete which constitutes the adjacent concrete slabs l6 and 17 of a bridge deck, as illustrated in FIGS. -1 and 2, or they may be formed from-metal members attached directly or indirectly to adjacent bridge deck portions. j j

The hollow, elongated, elastomer seal 10 embodies an elongated, elastomer top wall 20. The top wall, as

:viewed in transverse cross section or end elevation,-has a trough-like configuration. ,It is composed of. elongated, substantially symmetrical segments 21 and 22 which extend downwardly from the upper edges of the side walls 24 and 25 and meet at a longitudinally extending junction 23. I

The side walls 24 and 25 are elongated, elastomer,

substantially flat or planar walls having a vertical orientation. Minor transverse curvatures, such as result from extrusion variations from the substantially flat or planar form, are not objectionable, cf. FIG. 3. The bottom wall 26 completes the hollow shell formed by the outer walls of the elastomer seal 10. Thebottom wall 26 is sume a downwardly directed V-shaped orientation as the seal approaches the full state of lateral collapse in the joint (FIG. 2). It is contemplated, however, that the center section 27 and/or the later described cross web 44 may assume an invertedV-configuration as the seal approaches the state of full lateral collapse in the joint.

The remainder of the bottom wall 26 comprises elongated, elastomer, longitudinal edge portions on each side of the center segment 27. These longitudinal edge portions are preferably symmetrical and are substantial mirror images of each other. The longitudinal edge .portions comprise, when the seal is not laterally compressed (FIG. 3) of elastomer, elongated leg segments 28 directed inwardly and slightly downwardly from the lower edges of the side walls 24 and 25 to a juncture 30 with the more acutely downwardly extending longitudinal leg portions 29. I

The elastomer seal 10 is inserted in a joint in the laterally compressed state and remains in varying degrees of lateral compression throughout opening and cross section, cf. FIG. 3 and FIG. 1. The apices thereof at the juncture 30 form longitudinally extending, seats which rest upon the respective ledges or seats 14 and 15 (FIG. 1 This function is of assistance in placing the elastomer seal 10 at the desired depth of insertion in the joint.

As the seal approaches its maximum lateral compression (FIG. 2), the shorter legs 29 are pushed or twisted into a substantially horizontal orientation so that they lie substantially flat on the upper face of the ledges or seats 14 and 15. The latter at the same time are moving closer together by virtue of closing of the joint. The longer legs 28 simultaneously are progressively becoming more and more oriented in the vertical plane of the side walls 24 and 25 until the latterreach a configuration substantially as shown in FIG. 2, i.e., with a relatively sharp bend immediately adjacent the juncture 30. This has the'effect of, at'most, a minor increase in the overall vertical distance between the top edges of the side walls 24 and 25 and the respective bottoms of the apices at the juncture whereby the upward creep? of the seal is minimized as the joint closes.

The internal web structure of the seal 10 comprises an integrated set of webs adapted to provide lateral thrust of the side walls 24 and 25 against the faces 12 and 13 of the joint 11. This internal web structure comprises downwardly diverging legs 32 and 33 connected at their upper ends to a vertical, narrow, longitudinally extending web or leg 31. The leg 31 is also joined with the longitudinal midportion 23 of the top wall 20.

' The downwardly diverging, elongated, longitudinally extending legs 32 and 33 may be substantially flat or planar legs or they may have, as illustrated, an angulation as viewed in transverse cross section or end elevation. In the latter instance they comprise more sharply diverging, upper leg segments 34 and 35 and less diverging leg segments 36, 36a, 37 and 37a. The leg segments 36 and 36a preferably are coplanar as are the leg segments 37 and 37a or they may have a slight difference in the respective angularities of their planes.

The lower, longitudinal edges of the diverging legs 32 and 33 are joined with the bottom wall 26 inwardly of the aforesaid longitudinal edge portions and preferably at the longitudinal junctures 45 and 46 of the center segment 27 and the shorter legs 29 of bottom wall 26.

The remainder of the internal structure of the seal comprises laterally directed legs or webs 38 and 39. The latter slope in the transverse direction upwardly and outwardly from the junctures 40 and 41 of legs or segments 34,36 and 35,37, respectively. The upwardly and outwardly sloping legs 38 and 39 are preferably substantially planar or may have a slight transverse curvature. The remainder of the internal web structure of the seal comprises the three webs 42, 43 and 44. The side webs 42 and 43 also have an outward and upward orientation at the same or a lesser slope, preferably the latter, than the slope of webs 38 and 39. They are also substantially flat or planar but may have a slight transverse curvature. The center web 44 intersects the diverging legs 32 and 33 substantially opposite the junctures of the side webs 42 and 43 with said diverging legs. The center web 44 extends substantially horizontally and preferably has a shallow trough-like configuration as viewed in end elevation or transverse cross section in order to urge the leg to assume a deeper V- automatically. forms longitudinally extending seats.

which rest against the joint seats or ledges in the initial stages of lateral collapse of such seals. The seals further provide structures minimizing the upward creep" of such seals'in the joint as the joint closes.

The seal 20a of FIG. 4 is similar in most respects to the seal 20 of FIGS. 1'3. Where applicable, like numerals designate like parts. The center segment'27a of the bottom wall may be substantially planar (FIG. 4) or it may have the shallow U- or V-configuration like segment 27 (FIGS. 1-3). The top-wall of seal 20a is composed of a shallow V-shaped, medial segment 48 and substantially horizontal, edge segments 49 and 50. A pair of diagonally outwardly and downwardly sloping webs 51 and 52 extend respectively between intermediate portions 55 and 56 of the top wall, i.e., the

lines of juncture of medial segment 48 and edge segments 49 and 50, and intermediate portions 53 and 54 of the legs or webs 38 and 39. The intersections of webs 51 and 52 with the legs or webs 38 and 39 are preferably spaced from the side walls 24 and 25 and closer to the side walls than to the junctures 41 and 40 of legs or webs 38 and 39 with the diverging webs 34, 36 and 35,37, e.g., a spacing ratio in the order of 1:3 to 4. As can be seen inFIGS. 1-3, the top wall tends to fold progressively closer to the webs 38 and 39 as lateral collapse of the seal progresses. There is a tendency for the upper longitudinal corners of the seal to roll inwardly away from the joint faces 12 and l3. The diagonal webs 51 and 52 resist the aforesaid tendency of the top wall to approach the webs 38 and 39 r and thus exert a rotational moment on the upper corner portions of the seal in directions opposite to the respective roll tendencies-thereby keeping the upper longitudinal edges of the side walls pressed tightly, against formulation which is extrudable, and which, upon vulcanization, will be resistant to deterioration and/or loss of resilience after exposure to hot and cold weather conditions, sunlight, and like elements of nature in the use thereof in joints of pavement, air strips, and the like. Care should be exercised in selecting an elastomer formulation whereby the seal will retain its flexibility and elastic recovery force generation at the coldest temperatures to be encountered in the field. The presently best-known elastomer is neoprene: particularly the crystallization-resistant types thereof.

It is thought that the invention and its numerous attendant advantages will be fully understood from the foregoing description, and it is obvious that numerous changes may be made in the form, construction and arrangement of the several parts without departing from the spirit or scope of the invention, or sacrificing any of its attendant advantages, the form herein disclosed being a preferred embodiment for the purpose of illustrating the invention. v

The invention is hereby claimed as follows:

1. A hollow elastomer seal useful for sealing bridge joints comprising an elongated, hollow elastomer body having an elongated, elastomer top wall, and an elongated, elastomer bottom wall and elongated, elastomer side walls joined at their longitudinal edges with said top and bottom walls, and said bottom wall including a longitudinal midportion connected to the lower longitudinal edges of said side walls by longitudinal, downwardly extending, substantially'V-shaped, shallow foot portions.

2. An elastomer seal as claimed in claim 1 wherein said longitudinal midportion has a shallow-V or shallow-U transverse cross section adapted to fold downwardly when said seal is collapsed laterally.

3. An elastomer seal as claimed in claim 1, and elongated webmembers interconnecting said bottom, top and side walls, said web members including a pair of downwardly diverging webs connected at their lower edges to the longitudinal juncture of said longitudinal midportion and said foot portions.

4. A hollow'elastomer seal useful for sealing bridge joints comprising an elongated, hollow elastomer body having an elongated, elastomer top wall, and an elongated, elastomer bottom wall and elongated, elastomer side walls joined at their longitudinal edges with said top and bottom walls, and said bottom wall including a longitudinal midportion connected to the lower'longitudinal edges of said side walls by elongated, respective V-shaped foot portions adapted to fold into substantially V-shaped transverse cross section when said seal is collapsed laterally, said foot portions respective- 1y being composed of a first segment sloping downwardly from the respective lower longitudinal edges of said side walls and a second segment of more acute downward slope extending downwardly from the respective longitudinal edges of said longitudinal midportion.

5. An elastomer seal as claimed in claim 4,,and longitudinally extending web members connecting said bottom, top and side walls, said web members including a pair of downwardly diverging webs connected at their lower edges to the longitudinal juncture of said longitudinal midportion and said foot portions and connected directly or indirectly at their upper edges with the iongitudinal midportion of said top wall.

6. An elastomer seal as claimed in claim 4, and longitudinally extending web membersconnecting said bottom, top and side walls, said web members including a pair of downwardly diverging webs connected at their lower edges tothe longitudinal juncture of said longitudinal midportion and said foot portions and connected directly or indirectlyat their upper edges with the longitudinal midportion of said top wall, and'at least one additional pair of laterally extending webs connecting said diverging webs with said side walls.

7. An elastomer seal as claimed in claim 6, said top wall having a shallow, concave configuration and adapted to fold downwardly into a deeper concave-conf r tion on 1 teral coll se of aids al.

in ela s tome r seal as .c imed in claim 7,'and a pair of diagonally downwardly and outwardly sloping webs extending respectively between intermediate portions of the top wall and intermediate portions of the uppermost pair of laterally extending webs.

9. An elastomer seal as claimed in claim 8, wherein said additional pair of webs respectively intersect said laterally extending webs at junctures spaced from said side walls and closer to said side walls than to said diverging webs. 

1. A hollow elastomer seal useful for sealing bridge joints comprising an elongated, hollow elastomer body having an elongated, elastomer top wall, and an elongated, elastomer bottom wall and elongated, elastomer side walls joined at their longitudinal edges with said top and bottom walls, and said bottom wall including a longitudinal midportion connected to the lower longitudinal edges of said side walls by longitudinal, downwardly extending, substantially V-shaped, shallow foot portions.
 2. An elastomer seal as claimed in claim 1 wherein said longitudinal midportion has a shallow-V or shallow-U transverse cross section adapted to fold downwardly when said seal is collapsed laterally.
 3. An elastomer seal as claimed in claim 1, and elongated web members interconnecting said bottom, top and side walls, said web members including a pair of downwardly diverging webs connected at their lower edges to the longitudinal juncture of said longitudinal midportion and said foot portions.
 4. A hollow elastomer seal useful for sealing bridge joints comprising an elongated, hollow elastomer body having an elongated, elastomer top wall, and an elongated, elastomer bottom wall and elongated, elastomer side walls joined at their longitudinal edges with said top and bottom walls, and said bottom wall including a longitudinal midportion connected to the lower longitudinal edges of said side walls by elongated, respective V-shaped foot portions adapted to fold into substantially V-shaped transverse cross section when said seal is collapsed laterally, said foot portions respEctively being composed of a first segment sloping downwardly from the respective lower longitudinal edges of said side walls and a second segment of more acute downward slope extending downwardly from the respective longitudinal edges of said longitudinal midportion.
 5. An elastomer seal as claimed in claim 4, and longitudinally extending web members connecting said bottom, top and side walls, said web members including a pair of downwardly diverging webs connected at their lower edges to the longitudinal juncture of said longitudinal midportion and said foot portions and connected directly or indirectly at their upper edges with the longitudinal midportion of said top wall.
 6. An elastomer seal as claimed in claim 4, and longitudinally extending web members connecting said bottom, top and side walls, said web members including a pair of downwardly diverging webs connected at their lower edges to the longitudinal juncture of said longitudinal midportion and said foot portions and connected directly or indirectly at their upper edges with the longitudinal midportion of said top wall, and at least one additional pair of laterally extending webs connecting said diverging webs with said side walls.
 7. An elastomer seal as claimed in claim 6, said top wall having a shallow, concave configuration and adapted to fold downwardly into a deeper concave configuration upon lateral collapse of said seal.
 8. An elastomer seal as claimed in claim 7, and a pair of diagonally downwardly and outwardly sloping webs extending respectively between intermediate portions of the top wall and intermediate portions of the uppermost pair of laterally extending webs.
 9. An elastomer seal as claimed in claim 8, wherein said additional pair of webs respectively intersect said laterally extending webs at junctures spaced from said side walls and closer to said side walls than to said diverging webs. 